Access Control: Anonymous LDAP Bind

ABSTRACT

在沒有適當 access control 的情況下，執行一個包含用戶控制值的 LDAP 聲明，這會讓攻擊者訪問未授權的記錄。

若未經 authentication 便在匿名綁定下有效地執行 LDAP 查詢，會導致攻擊者濫用低端配置的 LDAP 環境。

例 1：以下代碼使用 ldap_simple_bind_s() 匿名綁定到一個 LDAP 目錄。


...
rc = ldap_simple_bind_s( ld, NULL, NULL );
if ( rc != LDAP_SUCCESS ) {
    ...
  }
...

針對 ld 執行的所有 LDAP 查詢都會在沒有 authentication 和 access control 的情況下執行。攻擊者可能會采取意想不到的方式操縱其中的某個查詢，以便可以訪問本應受目錄 access control 機制保護的記錄。

[1] Standards Mapping - OWASP Top 10 2007 - (OWASP 2007) A10 Failure to Restrict URL Access

[2] Standards Mapping - OWASP Top 10 2004 - (OWASP 2004) A2 Broken Access Control

[3] Standards Mapping - OWASP Top 10 2010 - (OWASP 2010) A8 Failure to Restrict URL Access

[4] Standards Mapping - FIPS200 - (FISMA) AC

[5] Standards Mapping - Security Technical Implementation Guide Version 3 - (STIG 3) APP3480.1 CAT I

[6] Standards Mapping - Security Technical Implementation Guide Version 3.4 - (STIG 3.4) APP3480.1 CAT I

[7] Standards Mapping - Common Weakness Enumeration - (CWE) CWE ID 285

[8] Standards Mapping - Web Application Security Consortium 24 + 2 - (WASC 24 + 2) Insufficient Authorization

[9] Standards Mapping - SANS Top 25 2009 - (SANS 2009) Porous Defenses - CWE ID 285

[10] Standards Mapping - SANS Top 25 2010 - (SANS 2010) Porous Defenses - CWE ID 285

[11] Standards Mapping - SANS Top 25 2011 - (SANS Top 25 2011) Porous Defenses - CWE ID 863

[12] Standards Mapping - Payment Card Industry Data Security Standard Version 1.2 - (PCI 1.2) Requirement 6.5.10, Requirement 7.2

[13] Standards Mapping - Payment Card Industry Data Security Standard Version 1.1 - (PCI 1.1) Requirement 6.5.2, Requirement 7.2

[14] Standards Mapping - Payment Card Industry Data Security Standard Version 2.0 - (PCI 2.0) Requirement 6.5.8, Requirement 7.2